Take a look at how the default Carenado A36 have implemented their lights. Dynamic Lights Enable/Disable option does not prevent lights from showing it only changes the rendering of the light.
In the SDK under "New Aircraft Procedures" take a look at "Landing Lights" - I believe you set the Visibility Objects to "general_light" and then in the FX file you specify will have the light type (Type=19). Unless of course you're doing custom lights via the PDK which is entirely different process. You actually don't want to specify Type=27 or 28 as those will ONLY show when DL is enabled (typically reserved for airport stationary lights). At least that's my understanding.
Here as an unlisted video of how DL On/Off should work relative the aircraft lights, in both cases you'll see that the lights do work, just render differently:
As far as cockpit textures, P3D V4 now supports (actually I think late in V3 this support was introduced) 4096 VC textures (default is 1024) ... this should help the visuals with dome lights but again I think you need to be careful what light type you're using for dome.
Cheers, Rob.

I solved the performance issues by turning OFF (uncheck) "Allow Hardware Rendering" and turn OFF Landing lights (DL is enabled) taxi light is fine but landing lights cause about a 35% FPS drop. I'm able to use landing lights with DL on PMDG, iFly, others without as much an FPS drop as I get in the 717. Perhaps the landing lights FX needs to be tuned a little bit for better performance?
So far no CTD. I don't have Chase Plane (a few items in CP need to be fixed before I'll install).
On a side note, the default livery seems to have some excessive specular, perhaps tone down the white?
Cheers, Rob.

Thanks for the responses, glad this issue is not specific to my setup and will be resolved.
The more worrying aspect is the strange performance I'm experiencing ... it has me puzzled, it's almost as if the gauge update rate is defining the FPS? Not seeing the issue in P3D V3 (very fluid), just in V4 which is odd because V4 operates about 15-20% better (in terms of FPS and less long frames) than P3D V3.
Cheers, Rob.

I just entered the TFDi Beta today for the 717 and took it for a test in P3D V4 (21686).
Installation went well. I had a issue with the iPAD and setting aircraft state, when I select Ready to Fly I got some pathing error that was pointing to A2A products? Please see attached error pic.
Performance seems odd, my FPS counter is solid at 30 FPS (Vsynch 30Hz monitor) but actual FPS is not 30, feels more like 15. I've never seen this issue before ... does the 717 operate outside of the stand physics modeling similar to the MJC Q400? If so, it looks like it's not synching up with P3D V4 correctly.
Cheers, Rob.